London Zoo: Chock full of animals. How can we tell? It takes keepers a week to count them all

Three giant Galapagos tortoises, a Komodo dragon and a critically endangered baby mangabey monkey are among the new residents at the central London zoo to be included in this year's annual head count.

The zoo's large population -- more than 14,500 animals, including thousands of insects -- means it will take keepers about a week to complete the census, which started today.

Other new additions include a pair of aardvarks and the first lion cubs born at the zoo in a decade.

The zoo says it hopes 70-year-old Galapagos tortoise Dirk and the Komodo dragon, a 7-year-old female from South Africa called Rinca, will mate -- each with its own kind -- and help boost the numbers further this year.